Forming device, machine, packaging laminate web, forming method and process in producing packages

ABSTRACT

A forming device and method for use in a packaging machine of the type where packages are produced from a tube. The forming device comprises two opposing sealing elements between which the tube is arranged to be flat-laid and squeezed to heat the thermoplastic and obtain a first transverse seal of the tube. It further comprises two volume control elements. The forming device is characterized in that it is arranged to displace the first transverse seal off-center in relation a longitudinal axis of the first portion of the tube in a displacement direction essentially perpendicular to the first transverse seal to enable later shaping of a corresponding final package with a wall arranged with a predetermined angle of inclination in relation to the displacement direction. The invention also relates to a machine, a process and a packaging laminate.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation of application Ser. No. 12/223,775filed Aug. 8, 2008, which is a National Stage of PCT/SE2007/000223 filedMar. 8, 2007, and claims priority to Swedish Application No. 0600731-4filed Mar. 31, 2006, the disclosures of all of which are incorporatedherein by reference in their entirety.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to a forming device and a forming methodfor use in a packaging machine of the type where individual packages areproduced from a tube of thermoplastic coated packaging laminate. Theinvention also relates to a machine for producing packages comprisingsuch a forming device, a packaging laminate web for producing packagesby means of such a forming device and a process for producing packagescomprising such a forming method. The forming device comprises twoopposing sealing elements between which the tube is arranged to beflat-laid and squeezed to heat the thermoplastic and obtain a firsttransverse seal of the tube, and two volume control elements arranged onopposite sides of the tube and having a releasing state in which thetube is movable in relation to the volume control elements and asecuring state for imparting a predetermined shape to the tube in afirst portion between the first transverse seal and a successive secondtransverse seal of the tube.

BACKGROUND ART

Within the food industry, beverages and other products are often packedin paper or paperboard based packages. Packages intended for liquid foodare often produced from a packaging laminate comprising a relativelyrobust core layer of paper or paperboard and an outer, liquid-tightlayer of thermoplastic material on at least that side of the core layerwhich will form the inside of the packages. For particularly oxygensensitive food products, such as fruit juice and cooking oil, thepackaging laminate usually further comprises a layer of a gas barriermaterial. This layer is in most cases an aluminum foil which alsoenables induction sealing of the packaging laminate.

The packages are often produced in a packaging machine where a web ofpackaging laminate is formed into a tube which is closed by sealing ofthe longitudinal edges of the web in an overlapping condition. Thelongitudinally sealed tube is continuously filled with a product andthen transversally sealed, wherein filled “cushions” are formed. Thetransverse sealing is made along narrow, transverse, mutually spacedapart, sealing zones. After the transverse sealing, the “cushions” areseparated from the rest of the tube by incisions in the sealing zonesand finally formed into the desired shape. The “cushions” can, as anexample, be formed, by mechanical folding, into parallelepiped-shapedpackages like the ones commercialized by the applicant under the nameTetra Brik or Tetra Brik Aseptic (registered trade marks).

A packaging machine of the above type is known from U.S. Pat. No.4,580,392. This packaging machine comprises alternately working formingand sealing jaws which are given a reciprocating movement in thelongitudinal direction of the tube and in the transverse direction ofthe tube. The sealing jaws are guided and driven by guiding and drivingrods which run parallel to the tube and to which different reciprocatingmovements are imparted. Attached to the sealing jaws are forming flapsdetermining the shape of the finished packing container and thereforealso its volume.

Packages are often provided with an opening device for facilitatingconsumption of the product in the package. Different types of openingdevices can be used, for example an opening device comprising a framefitted to the top wall of the package and defining an opening of thesame, and a removable cap hinged or screwed to the frame. The top wallof the package formed from the tube of packaging laminate will comprisea number of seals resulting from the longitudinal and transversesealing. Because of technical difficulties, it is not preferred toarrange the opening device in an area of a seal. Therefore, the amountof space available for positioning of the opening device on the top wallof the package is quite limited. As an example, in the case of a TetraBrik package, the top wall is centrally crossed by a transverse seal.Further, an end portion of the longitudinal seal extends centrallyacross half the top wall, perpendicularly from the transverse seal.Obviously, this limits the maximum size of the opening device used.However, in many situations a relatively large opening device isdesired. As an example, when the product to be packed is semiliquid orcontains fibres or larger particles, a bigger opening device is requiredto enable smooth pouring of the product.

Further, an opening device usually protrudes from the package which maybe drawback when it comes to stacking of the package. As an example, inthe case of Tetra Brik packages provided with a respective openingdevice on the top wall, stacking of the packages on top of each othermay be difficult. In a stack, the uppermost package will be supported bythe opening device on the second uppermost package and so on. Obviously,this is not a stable configuration, especially since the opening device,as apparent from above, is arranged off-center at the top wall and has alimited size.

To increase the space available for positioning of the opening device onthe top wall of the package it has been proposed to provide the frontedge of the top wall of the package, which front edge is opposite theedge of the top wall crossed by the longitudinal seal, with a convexC-shaped bend line or so-called “smile crease”, instead of a straightone. However, a package produced in accordance with this solution willnaturally not have the shape of a perfect parallelepiped because of theincreased top wall area. Instead, the front side wall of the package,which is adjacent to the front edge of the top wall, will be projectingin an area close to the C-shaped bend line. Further, the top wall willbe sloping downwards from the transverse seal to the C-shaped bend line.The more convex the bend line is, the more the package will differ fromthe parallelepiped-shape. Thus, the purpose of the C-shaped bend line isto enable the provision of a relatively large opening device on thepackage. With such a relatively large opening device, the abovediscussed stacking problems will most likely still be present. Further,there may also be problems relating to stowing of these “smile crease”packages in rows with the front side wall of one package facing theopposite back side wall of the neighboring package because of theprojection of the front side wall.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a forming device, amachine comprising such a forming device, a packaging laminate web foruse in connection with such a forming device, a forming method and aprocess comprising such a forming method which, at least partly,eliminate potential limitations of prior art. The basic concept of theinvention is to provide an opportunity for producing a package where theposition of one of the transverse seals have been moved from the centerso as to give the package an inclined top and/or bottom wall.

The forming device, machine, packaging laminate web, forming method andprocess for achieving the object above are defined in the appendedclaims and discussed below.

A forming device for use in a packaging machine of the type whereindividual packages are produced from a tube of thermoplastic coatedpackaging laminate, according to the present invention comprises twoopposing sealing elements between which the tube is arranged to beflat-laid and squeezed to heat the thermoplastic and obtain a firsttransverse seal of the tube. The forming device further comprises twovolume control elements arranged on opposite sides of the tube andhaving a releasing state in which the tube is movable in relation to thevolume control elements and a securing state for imparting apredetermined shape to the tube in a first portion between the firsttransverse seal and a successive second transverse seal of the tube. Theinventive device is characterized in that it is arranged to displace thefirst transverse seal off-center in relation a longitudinal axis of thefirst portion of the tube in a displacement direction essentiallyperpendicular to the first transverse seal to enable later shaping of acorresponding final package with a wall arranged with a predeterminedangle of inclination in relation to the displacement direction.

One advantage with the present invention is that already existingforming devices for holding and sealing a tube of packaging laminate canbe modified so as to embody the inventive way of handling the tube. Forexample, the positioning and/or movement, in relation to the tube, ofthe sealing jaws and forming flaps could be altered in the initiallydiscussed known machine.

As the name indicates, the volume control elements are arranged to makesure that the final packages contain the desired volume of product bypressing onto the tube in a predetermined way in the securing state inconnection with transverse sealing.

The successive second transverse seal, and therefore the first portionof the tube, can be arranged on either side of the first transverseseal, i.e. upstream or downstream there from.

The first and second transverse seals are arranged to be cut at a laterstage, as initially mentioned, to each form a top transverse seal and abottom transverse seal of two final consecutive packages.

Said first portion of the tube is arranged to form a piece of the finalpackage limited by the top and bottom transverse seals.

The forming device according to the present invention is advantageoussince it makes it possible to, in a fast and neat way, produce packageswith a respective inclining wall having a relatively large spaceavailable for positioning of an opening device. The inclining wall givesthe package, when this is provided with a suitable opening device,better stacking possibilities. Additionally, in connection with thispackage, the initially described problems related to stowing can beeliminated.

As an example, the inventive forming device can be constructed so as toenable later shaping of a corresponding final package with a wallarranged with a predetermined angle of inclination in relation to anopposite wall.

According to one embodiment, the sealing elements are arranged to movetowards and apart from each other parallel to the displacement directionbeing essentially perpendicular to a sealing element center axis beingessentially perpendicular to the first transverse seal and extendingbetween the sealing elements. Further, the sealing element center axisis tilted in relation to the longitudinal axis of the first portion ofthe tube when the volume control elements are in the securing state toachieve the displacement of the first transverse seal.

A forming device according to the paragraph above can be constructed insuch a way that the sealing element center axis is tilted in relation tothe longitudinal axis of the first portion of the tube when the volumecontrol elements are in the releasing state and in relation to alongitudinal axis of a second portion of the tube when the volumecontrol elements are in the releasing state and in the securing state.The first and second portions of the tube are arranged on opposite sidesof the second transverse seal, and the longitudinal axes of the firstand second portions of the tube coincide when the volume controlelements are in the releasing state and in the securing state. Thus, inother words, this embodiment is based on tilting the tube in relation tothe center axis of the sealing elements from the first transverse sealand upstream or downstream depending on the arrangement of the secondtransverse seal in relation to the first transverse seal. Naturally,either of the positioning of the tube or the positioning of the sealingelements can be altered to achieve the desired relative tilt.

Alternatively, the forming device can be constructed in such a way thatthe sealing element center axis is essentially parallel to thelongitudinal axis of the first portion of the tube when the volumecontrol elements are in the releasing state and in relation to alongitudinal axis of a second portion of the tube when the volumecontrol elements are in the releasing state and in the securing state.Like above, the first and second portions of the tube are arranged onopposite sides of the second transverse seal. However, the longitudinalaxes of the first and second portions of the tube are here tilting inrelation to each other when the volume control elements are in thesecuring state. Thus, this embodiment is based on “cracking” or“bending” the tube between the first and second portions of the same inconnection with sealing. Thereby, when the volume control elements arein the securing state, the tube will be tilting in relation to thecenter axis of the sealing elements from the first transverse seal tothe second transverse seal, whereas the tube will remain straight fromthe second transverse seal and upstream or downstream depending on thearrangement of the second transverse seal in relation to the firsttransverse seal. An advantage with this embodiment is that alreadyexisting forming devices can be modified in a mechanically simple way toachieve a forming device according to the present invention.

The above discussed “cracking” or “bending” of the tube can, as anexample, be achieved by a forming device further constructed so that thevolume control elements are arranged to move from the releasing state tothe securing state to move, in connection with sealing, the firstportion of the tube from a state where its longitudinal axis isessentially parallel to the sealing element center axis and coincideswith the longitudinal axis of the second portion of the tube to a statewhere the longitudinal axis of the first portion of the tube is tiltedin relation to the sealing element center axis and the longitudinal axisof the second portion of the tube. Thus, this embodiment is based ondeforming the tube by means of the volume control elements. Thedeformation could, e.g., be achieved by having differently shaped volumecontrol elements or volume control elements journaled in differentpositions in relation the respective corresponding sealing elements.

According to another embodiment, just like above, the sealing elementsare arranged to move towards and apart from each other parallel to thedisplacement direction being essentially perpendicular to a sealingelement center axis being essentially perpendicular to the firsttransverse seal and extending between the sealing elements. However,according to this embodiment, the sealing elements are further arrangedto move together in the displacement direction when the volume controlelements are in the securing state to obtain a transverse movement ofthe sealing element center axis and achieve the displacement of thefirst transverse seal. Thus, this embodiment is based on transversallymoving the sealing elements in a common motion in connection withtransverse sealing, which elements are kept still in relation to eachother during the motion. One advantage with this embodiment is that itenables relatively mild handling of the packaging laminate since notilting and/or bending of the tube is necessary.

A forming device according to the present invention can be constructedso as to further comprise a shaping element arranged to press on thefirst portion of the tube to fold two opposing wall sections of thefirst portion along a respective folding line with the predeterminedangle of inclination in relation to the displacement direction. Thisfolding line can be imaginary but may coincide with a weakening line, aso-called crease line, if present, in the packaging laminate.

The shaping element can have any suitable shape, such as the shape of aplate or flap.

This embodiment is advantageous since it facilitates the later shapingof a corresponding final package with an inclined wall. As apparent fromabove, the folding lines will be parallel to the inclined wall of thefinal package.

The shaping element can be formed with a folding surface arranged topress on the first portion of the tube along one of the folding lines.If the shaping element is formed like a plate or a flap, the foldingsurface can be arranged along one edge of this plate or flap.

Further, the shaping element can be rotatable around an axis to move thefolding surface into and out of contact with the first portion of thetube. The axis is, according to one embodiment, essentially parallel tothe displacement direction when the volume control elements are in thesecuring state, which enables a relatively mechanically simpleconstruction of the inventive device. According to another embodiment,the axis is instead essentially parallel to the folding lines when thevolume control elements are in the securing state. An advantage withthis design is that it enables a parallel arrangement of the part of theshaping element contacting the tube and the folding lines. Naturally,different directions of the axis of rotation mean different designs ofthe shaping element.

Besides for being rotatable around an axis, the shaping element may bemovable along the axis to reduce friction between the shaping elementand the tube during folding. Naturally, this embodiment is advantageoussince it enables a more gentle handling of the tube which, in turn,reduces the risk of damaging the packaging laminate.

A machine for producing packages, according to the present invention,comprises a forming device as described above.

A packaging laminate web according to the present invention, for formingsaid tube for producing said individual packages by means of a formingdevice as described above, comprises a crease pattern corresponding toone package and repeating itself along the web. The final packages eachcomprises a front wall, a back wall, first and second opposing sidewalls, a bottom wall and a top wall, and in accordance therewith, thecrease pattern comprises a front crease line defining an extension ofthe front wall in a longitudinal direction of said final packagepointing towards the top wall and being parallel to the longitudinalaxis of the first portion of the tube, a back crease line defining anextension of the back wall in said longitudinal direction, a first sidecrease line defining an extension of the first side wall in saidlongitudinal direction and a second side crease line defining anextension of the second side wall in said longitudinal direction. Thefirst and second side crease lines are inclined in relation to atransverse direction of the web.

The crease pattern facilitates the shaping of a final package into thedesired form, i.e. the shaping of a package with an inclined wall.

A forming method for use in a packaging machine of the type whereindividual packages are produced from a tube of thermoplastic coatedpackaging laminate, according to the present invention, comprisessqueezing the tube in a flat-laid condition between two opposing sealingelements to heat the thermoplastic and obtain a first transverse seal ofthe tube. The forming method further comprises imparting, by means oftwo volume control elements arranged on opposite sides of the tube andbeing in a securing state, a predetermined shape to the tube in a firstportion between the first transverse seal and a successive secondtransverse seal of the tube. The volume control elements have, besidesfor the securing state, a releasing state in which the tube is movablein relation to the volume control elements. The inventive method ischaracterized in that it further comprises displacing the firsttransverse seal off-center in relation a longitudinal axis of the firstportion of the tube in a displacement direction essentiallyperpendicular to the first transverse seal to enable later shaping of acorresponding final package with a wall arranged with a predeterminedangle of inclination in relation to the displacement direction.

A process for producing packages, according to the present invention,comprises a forming method as described above.

The characteristics discussed in connection with the inventive formingdevice are, of course, transferable to the inventive machine, packaginglaminate web, forming method and process. Further, these characteristicsmay naturally be combined in the same embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described in more detail with reference to theappended schematic drawings, which show examples of presentlynon-limiting preferred embodiments of the present invention.

FIG. 1 is a schematic front view, with parts removed for clarity, of aninventive machine for producing packages.

FIG. 2 is a schematic side view of two forming devices of the machine inFIG. 1 according to a first embodiment of the present invention.

FIG. 3 is a schematic side view of two forming devices of the machine inFIG. 1 according to a second embodiment of the present invention.

FIG. 4 is a schematic side view of two forming devices of the machine inFIG. 1 according to a third embodiment of the present invention.

FIG. 5 is a side view of a final package that can be manufactured bymeans of a machine according to FIG. 1.

FIG. 6 is a front view of a sheet of packaging laminate corresponding tothe package in FIG. 5.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

In FIG. 1, a machine 10 for producing packages 12 from a tube 14 ofpackaging laminate is shown. The packaging laminate is of the initiallydescribed kind, i.e. it comprises a paper core layer, an aluminum gasbarrier layer and outer layers of thermoplastic material. As initiallydescribed, the tube 14 is formed by sealing of the longitudinal edgesections of a web 16 of packaging laminate in an overlapping condition.After forming, the tube 14 is filled with the intended product.Continuous forming and filling of a tube like this is well-known andwill not be described in detail herein.

After forming and filling, the tube 14 is fed to a forming unit 18. Theforming unit 18 comprises two guides 20 arranged on opposite sides ofthe tube 14, and two forming devices 22, 22′ which are slidably movablealong the respective guides 20, between an upper end point and a lowerend point on the guides. The forming devices are alternately interactingwith the tube 14 to transversally seal it at regular intervals. As willbe further discussed below, each transverse seal will, after cutting,form a top transverse seal and a bottom transverse seal of two finalconsecutive packages. Since the forming devices are essentiallyidentical, the rest of the description will be directed mainly towardsone of them, the forming device 22.

The forming device 22 comprises two sealing jaws 24, 26 and twocorresponding volume control elements 28, 30 arranged on opposite sidesof the tube 14. In turn, the jaws each comprise a main body 32, 34 and asupport arm 36, 38 attached thereto and projecting sideways there from.In FIG. 1, only the sealing jaw 24, the volume control element 28, themain body 32 and the support arm 36 can be seen. The support arms ofeach sealing jaw carry a respective elongate sealing element (not shownin FIG. 1) between which the tube 14 is arranged to be flat-laid andsqueezed to heat the thermoplastic by induction and obtain a transverseseal of the tube. The forming devices 22, 22′ produce every othertransverse seal so that, as an example, the forming device 22 producesthe first, third and fifth seal, etc., whereas the forming device 22′produces the second, fourth and sixth seal, etc. In connection withtransverse sealing, the volume control elements 28, 30 are arranged toact on the tube 14 to impart a predetermined shape to it in a portionbetween two successive transverse seals. Thus, the construction of thevolume control elements determines the volume of the final packages.

The jaws 24, 26 are pivotable about a respective axis arranged at thebottom of the main body 32, 34 parallel to the direction X shown inFIG. 1. Further, the jaws of the forming device 22 are arranged to pivotin opposite directions to change the state of the forming device. Theforming device 22, and therefore the volume control elements 28, 30, hasa releasing state in which the jaws 24, 26 and the volume controlelements 28, 30 are inclined away from each other and a securing statein which the jaws and the volume control elements are arrangedessentially parallel to each other. In the releasing state, the volumecontrol elements do not contact the tube 14 which is moveable inrelation to them. In the securing state, the volume control elementscontact the tube from opposite directions. The forming device 22 followsa predetermined cycle to achieve one single transverse seal. This cyclebegins when the forming device 22 is arranged at the upper end point onthe guide 20. The state of the forming device 22 then changes from thereleasing state to the securing state. In connection therewith, the tube14 is locked, first between the sealing elements and then also betweenthe volume control elements 28, 30. Then, the forming device 22 movesdownwards along the respective guide 20 and pulls the tube 14 along withit whereby a transverse seal is obtained. When the forming devicereaches the lower end point on the respective guide 20, it changes itsstate from the securing state to the releasing state. Further, it startsmoving in the opposite direction, i.e. upwards along the guide 20. Whenthe forming device reaches the upper end point on the guide 20 the cycleis completed. The forming device 22′ follows a similar, but timeshifted, cycle to achieve one single transverse seal. The time shiftequals half a cycle duration time which means that one of the formingdevices 22, 22′ always will be in the securing state to feed the tubecontinuously downwards. When the forming device 22 moves upwards fromthe lower end point to the upper end point, the forming device 22′ willpass between the volume control elements 28, 30 and the sealing jaws 24,26, or more exactly the sealing elements thereof, of the forming device22, and vice versa.

First, second and third exemplary embodiments of the forming devices 22,22′, denoted 22 a-22 c and 22 a′-22 c′, are shown in more detail inFIGS. 2, 3 and 4, respectively. By means of these forming devices, finalpackages, like the package 40 illustrated in FIG. 5, can be produced inthree different ways. The package 40 comprises a front wall 31, a backwall 33, first and second opposing side walls 35 of which only thesecond one can be seen in the figure, a bottom wall 39 and a top wall41. In FIG. 6, a sheet 42 of packaging laminate, corresponding to thesingle package 40, is shown. The sheet 42 comprises a specific creasepattern 44 composed of weakening lines or crease lines determining wherethe sheet should be folded to obtain the final package shape shown inFIG. 5. The crease pattern 44 comprises four longitudinal crease lines43, 45, 47 and 49 dividing the sheet 42 into five portions 51, 53, 55,57 and 59. It further comprises a transverse bottom crease line 61 and atop crease line 63 dividing each of the sheet portions into three subportions 51 a-c, 53 a-c, 55 a-c, 57 a-c and 59 a-c. The sub portions 51a, 55 a and 59 a are arranged to form together the top wall 41, whilethe sub portions 51 c, 55 c and 59 c are arranged to form together thebottom wall 39, of the package 40. Further, the sub portions 51 b and 59b are arranged to form together the back wall 33, while the sub portions53 b, 57 b and 55 b are arranged to form the first and second side walls35 and the front wall 31, respectively, of the package 40. In fact, thetop crease line 63 is composed of five sub crease lines, one for each ofthe sheet portions: a first back crease line 63 a, a first side creaseline 63 b, a front crease line 63 c, a second side crease line 63 d anda second back crease line 63 e. As apparent from FIG. 6, the front andback crease lines 63 c and 63 a+e are essentially parallel to the bottomcrease line 61 while the side crease lines 63 b and 63 d are arrangedwith a predetermined angle of inclination β in relation to the frontcrease line. Further, the back crease lines are arranged at a largerdistance from the bottom crease line than the front crease line whichmeans that the extension of the back wall of the final package in alongitudinal direction L of the final package will be larger than theextension of the front wall.

The package 40 also includes two opposing triangular top flaps 65 ofwhich only one can be seen in FIG. 5 and two opposing triangular bottomflaps (not shown and not further discussed herein). In accordancetherewith, the crease pattern 44 further includes one pair of top flapcrease lines 67, 69 and 71, 73 associated with each of the first andsecond side crease lines 63 b and 63 d. More particularly, the top flapcrease lines 67 and 69 associated with the first side crease line 63 bextend in the sub portion 53 a, upwards and towards each other from arespective end of the first side crease line. Similarly, the top flapcrease lines 71 and 73 associated with the second side crease line 63 dextend in the sub portion 57 a, upwards and towards each other from arespective end of the second side crease line. The sub portion 53 a isarranged to form the top flap not shown in FIG. 5, which is composed oftwo layers of packaging laminate, one of the layers extending from thetop wall and the other layer extending from the first side wall of thefinal package 40. Correspondingly, the sub portion 57 a is arranged toform the top flap shown in FIG. 5, which is composed of two layers ofpackaging laminate, one layer extending from the top wall and the otherlayer extending from the second side wall of the final package 40. Onceformed, the top flaps 65 are foldable along the respective first andsecond side crease lines 63 b and 63 d and thereafter attachable to therespective first and second side walls 35. As apparent form the figures,the top flap crease lines 67 and 69 together with the first side creaseline 63 b define the three edges of one of the triangular top flapswhile the top flap crease lines 71 and 73 together with the second sidecrease line 63 d define the three edges of the other one.

The sheet further comprises a temporarily sealed hole 46 for subsequentapplication of a suitable opening device 48. The edge portions 50 and 52are arranged to be joined together in an overlapping condition forlongitudinal sealing of the sheet and, thereby, forming of a tubularsleeve, while the edge portions 54 and 56 are arranged for a respectivetransverse sealing of this sleeve. The continuous web 16, which is shownin FIG. 1, consists of a long succession of sheets 42 adjoining eachother at the respective edge portions 54 and 56. The web has mutuallyopposing longitudinal edge sections arranged to be joined together in anoverlapping condition for forming of a longitudinal seal and thereby thetube 14, as previously mentioned. As apparent from the text above andthe figures, the longitudinal seal will extend across the back wall andparts of the top and bottom walls of the final package. Obviously, theedge portions 50 and 52 are comprised in a respective one of theselongitudinal edge sections and said sleeve forms a part of the tube.Further, the web has first, second, third, fourth, and so on, transversesealing zones which are parallel to a transverse direction of the weband intended for the first, second, third, fourth, and so on, transverseseals of the tube, respectively. Obviously, the edge portions 54 and 56constitute a respective half of two successive ones of these transversesealing zones. For reasons of simplicity, the crease pattern and theprelaminated hole of the respective sheets cannot be seen in the otherfigures.

Thus, in FIG. 2, the forming devices 22 a and 22 a′ according to a firstembodiment of the invention are shown. The forming device 22 a′ isarranged in its releasing state while the forming device 22 a isarranged in its securing state to squeeze and heat the tube 14 betweenits sealing elements 58 and 60 to obtain a first transverse seal. Inconnection with this transverse sealing, a first portion 62 of the tubeis held between the volume control elements 28, 30. Later on, asdescribed above, the forming device 22 a will adopt its releasing statewhereas the forming device 22 a′ will adopt its securing state tosqueeze and heat the tube 14 between its sealing elements 58′ and 60′ toobtain the second transverse seal. In connection with this transversesealing, the tube will be held between the volume control elements 28′and 30′.

As apparent from FIG. 2, the tube 14 is tilting by an angle α inrelation to a vertical sealing element center axis S from the firsttransverse seal and upwards. Thus, the longitudinal axis 64 of the firstportion 62 of the tube 14 deviates from the sealing element center axisS. Obviously, the longitudinal axis 66 of a second portion 68 of thetube arranged upstream from the second transverse seal also deviatesfrom the sealing element center axis S but coincides with thelongitudinal axis 64 of the first portion 62. In accordance therewith,to enable holding of the tilting tube, the essentially identical volumecontrol elements 28, 30 of the forming device 22 a are journaled atdifferent heights from the respective sealing elements 58, 60. The jaws24, 26 are arranged to rotate about respective shafts 70, 72symmetrically arranged on opposite sides of the sealing element centeraxis S. Accordingly, the sealing elements 58, 60 move towards and apartfrom each other in a direction perpendicular to the first transverseseal. Similarly, the sealing elements 58′, 60′ move towards and apartfrom each other in a direction perpendicular to the second transverseseal, which is parallel to the first transverse seal, as illustrated bythe arrow M in FIG. 2.

Each of the forming devices 22 a, 22 a′ further comprises two shapingelements arranged on opposite sides of the volume control elements 28,28′ attached to the arms of the respective jaws. Only one shapingelement per forming device, denoted 74 and 74′, can be seen in FIG. 2.The shaping elements of the forming device 22 a are arranged to press,with a respective folding surface thereof, on two opposing wall sectionsof the first portion 62 of the tube 14 in connection with transversesealing to fold them along a respective imaginary folding linecoinciding with a respective one of the first and second side creaselines 63 b and 63 d. Only the folding surface 75′ of the shaping element74′ can be seen in FIG. 2. The shaping element 74 is composed of afolding flap arranged to rotate around an axis F, which is essentiallyhorizontal when the forming device is in its securing state, to switchbetween a raised state and a lowered state. The shaping element isarranged to be in the raised state, which means no contact with the tube(like shaping element 74′ in FIG. 2), when the forming device is in itsreleasing state, and in the lowered state, which means contact with thetube along the folding line (like shaping element 74 in FIG. 2), whenthe forming device is in its securing state. Thus, as the nameindicates, the purpose of the shaping elements is to facilitate theshaping of the tube.

The tilting of the tube together with the construction of the volumecontrol elements, the sealing elements and the shaping elements willresult in a displacement of the first transverse seal off-center inrelation the longitudinal axis 64 of the first portion 62 (and, thus,the longitudinal axis 66 of the second portion 68) of the tube 14 in adisplacement direction D essentially perpendicular to the firsttransverse seal. This enables, as will be further discussed below, latershaping of a corresponding package 40 with a top wall 41 having apredetermined angle β of inclination in relation to the displacementdirection D or in relation to the opposing wall of the package, here thebottom wall 31.

In the above described embodiment, the displacement of the firsttransverse seal is achieved by tilting the tube and the volume controlelements in relation to the vertical sealing element center axis. Sincethe tilting is relative, the same displacement can naturally be achievedin other ways, e.g. by tilting the sealing element center axis inrelation to a vertical tube and volume control elements arrangedsymmetrical with respect to the vertical direction.

In FIG. 3, the forming devices 22 b and 22 b′ according to a secondembodiment of the invention are shown. The states of the forming devices22 b and 22 b′ in FIG. 3 are the same as the states of the formingdevices 22 a and 22 a′ in FIG. 2. Just like in FIG. 2, the formingdevices 22 b, 22 b′ are arranged to make first and second transverseseals of the tube 14, respectively. To this end, like in FIG. 2, thejaws 24, 26 are arranged to rotate about the symmetrically arrangedrespective shafts 70, 72 to move the sealing elements 58, 60 towards andapart from each other in a direction perpendicular to the firsttransverse seal. The corresponding movement of the sealing elements 58′,60′ is illustrated by the arrow M in FIG. 3. Further, a first portion 62of the tube 14 is arranged to be held between the volume controlelements 28, 30 of the forming device 22 b in connection with sealing.

As apparent from FIG. 3, in an unaffected condition, the longitudinalaxis 64 of the first tube portion 62, as well as the longitudinal axis66 of the second tube portion 68, coincides with the vertical sealingelement center axis S. However, just like in the previously describedembodiment, the essentially identical volume control elements 28, 30 ofthe forming device 22 b are journaled at different heights from therespective sealing elements 58, 60. Therefore, in accordance with thissecond embodiment, when the forming device 22 b changes its state fromthe releasing state to the securing state, the volume control elements28, 30 will move the first portion 62 from a position where itslongitudinal axis 64 coincides with the sealing element center axis Sand with the longitudinal axis 66 of the second portion 68 of the tube14, to a position where the longitudinal axis of the first portion ofthe tube is tilted by an angle α in relation to the vertical sealingelement center axis and the longitudinal axis of the second portion ofthe tube. Thus, in connection with transverse sealing, the tube is bentbetween the first and second portions so as to make the first tubeportion tilt in relation to the rest of the tube.

Each of the forming devices 22 b, 22 b′ further comprises two shapingelements arranged on opposite sides of the volume control elements 28,28′ attached to the arms of the respective jaws. Only one shapingelement per forming device, denoted 74 and 74′, can be seen in FIG. 3.The shaping elements of the forming device 22 b are composed of arespective folding flap constructed just like the forming flaps of theforming device 22 a described above with one exception. In addition tobeing arranged to rotate around an axis F, which is essentiallyhorizontal when the forming device is in its securing state, to switchbetween a raised state and a lowered state, the folding flap is arrangedto move along the axis F during the switch between the raised andlowered states so as to be more projecting from the respective arm inthe lowered state (like shaping element 74 in FIG. 3) than in the raisedstate (like shaping element 74′ in FIG. 3). This movement along the axisis advantageous since it reduces the friction between the tube and theshaping elements during folding of the opposing wall sections of thefirst tube portion along the respective folding lines.

The bending of the tube together with the construction of the volumecontrol elements, the sealing elements and the shaping elements willresult in a displacement of the first transverse seal off-center inrelation the longitudinal axis 64 of the first portion 62 of the tube 14in a displacement direction D essentially perpendicular to the firsttransverse seal. This enables, as will be further discussed below, latershaping of a corresponding package 40 with a top wall having apredetermined angle β of inclination in relation to the displacementdirection D.

In FIG. 4, the forming devices 22 c and 22 c′ according to a thirdembodiment of the invention are shown. The states of the forming devices22 c and 22 c′ in FIG. 4 are the same as the states of the formingdevices 22 a and 22 a′ in FIG. 2. Just like in FIG. 2, the formingdevices 22 c, 22 c′ are arranged to make first and second transverseseals of the tube 14, respectively. Further, a first portion 62 of thetube 14 is arranged to be held between the volume control elements 28,30 of the forming device 22 c in connection with sealing.

As apparent from FIG. 4, the longitudinal axis 64 of the first tubeportion 62, as well as the longitudinal axis 66 of the second tubeportion 68, are parallel to the vertical sealing element center axis S(S₁, S₂). In contrast to the two above described first and secondembodiments, the essentially identical volume control elements 28, 30 ofthe forming device 22 c are journaled at the same height from therespective sealing elements 58, 60. Like in the previously describedembodiments, the jaws 24, 26 are arranged to rotate about the respectiveshafts 70, 72, which are symmetrically arranged on opposite sides of thevertical sealing element center axis S₁, to move the sealing elements58, 60 towards and apart from each other in a direction perpendicular tothe first transverse seal. The corresponding movement of the sealingelements 58′, 60′ is illustrated by the arrow M in FIG. 4. However,unlike the support arms 36, 38 of the above described forming devices 22a, 22 b, the support arms 36, 38 of the forming device 22 c are notfixedly attached to the respective main bodies 32, 34. Instead, the arms36, 38 of the forming device 22 c are arranged to be displaced in thetransverse direction in relation to the respective main bodies 32, 34when the forming device 22 c is in the securing state. Since the sealingelements 58 and 60 are supported by the respective arms 36, 38, theywill also be displaced in the transverse direction in connection withsealing to obtain the first transverse seal. Initially in the securingstate of the forming device 22 c, the sealing elements 58, 60 will bearranged so as to have a sealing element center axis S₁, which, asapparent from FIG. 4, coincides with the longitudinal axis 64 of thefirst tube portion 62, as well as the longitudinal axis 66 of the secondtube portion 68. At the end of the securing state of the forming device22 c, the sealing elements will have moved together in the transversedirection so as to have a sealing element center axis S₂ which, asapparent from FIG. 4, is transversally displaced in relation to thelongitudinal axes 64, 66 of the first and second tube portions 62, 68,respectively.

Each of the forming devices 22 c, 22 c′ further comprises two shapingelements arranged on opposite sides of the volume control elements 28,28′ attached to the arms of the respective jaws. Only one shapingelement per forming device, denoted 74 and 74′, can be seen in FIG. 4.The shaping elements of the forming device 22 c are composed of arespective folding flap constructed just like the forming flaps of theforming device 22 a described above with one exception. The axis Faround which the folding flap is arranged to rotate is not essentiallyhorizontal but instead tilted so as to be parallel to the respectivefolding line when the forming device is in its securing state. Further,since the folding flap is attached to the support arm 36 of the formingdevice 22 c, it will also be displaced in the transverse direction inconnection with sealing. This transverse displacement can be compared tothe movement along the axis of the folding flap of the forming device 22b according to the second embodiment, and it gives the same advantages.

The transverse movement of the sealing element center axis together withthe construction of the volume control elements, the sealing elementsand the shaping elements will result in a displacement of the firsttransverse seal off-center in relation the longitudinal axis 64 of thefirst portion 62 of the tube 14 in a displacement direction Dessentially perpendicular to the first transverse seal. This enables, aswill be further discussed below, later shaping of a correspondingpackage 40 with a top wall having a predetermined angle β of inclinationin relation to the displacement direction D.

Thus, the present invention enables production of the package 40 shownin FIG. 5. The center part 78 of the package corresponds to the abovereferenced first tube portion 62. Further, the top transverse seal 80and bottom transverse seal (not shown) correspond to the abovereferenced first and second transverse seals cut in half, respectively.The top wall 41 of the package 40 has a predetermined angle β ofinclination in relation to the bottom wall 39. Naturally, as apparentfrom the above, the same angle can be identified between each of thefolding lines, and thus, the first and second side crease lines 63 b and63 d, and the bottom crease line 61 in FIG. 6. Since the top transverseseal 80 is not centrally positioned on the top wall 41 but displacedoff-center, the area available for application of an opening device 48on the top wall is considerably increased. Thus, the package can beprovided with a relatively large opening device which makes it suitablealso for semiliquid products and products containing fibres and largerparticles. Further, this relatively large opening device can be providedon the package without having to change the cross section of thepackage, from being rectangular, in a plane parallel to the bottom wall39, like in the case with the initially described “smile crease”package. In accordance therewith, the provision of large opening deviceson the packages does not result in problems relating to stowing of thepackages in rows and columns.

Additionally, as apparent from FIG. 5, the dimensions of the openingdevice to be applied onto the package can be chosen so that the highestpoint on the opening device 48, the point denoted 88, lies inessentially the same plane as the highest edge of the package 40, theedge denoted 90, when the package is in its normal state oftransportation. Naturally, this greatly reduces the initially describedproblems associated with stacking of the packages on top of each other.In a stack, the uppermost package will be supported by the point 88 ofthe opening device and the edge 90 of the second uppermost package andso on. Obviously, this is a relatively stable configuration, especiallysince the support point 88 and the support edge 90 are well separated.

Naturally, the more off-centered the top transverse seal 80 is on thetop wall 41 of the package 40, the more inclined the top wall is, andthe more space is available for positioning of an opening device 48 onthe top wall. However, in connection with packages of the abovedescribed type, there is a limit to how much the transverse seal can beoff-centered without changing the package design of principle. In fact,FIG. 5 illustrates the extreme case with the top transverse sealoff-centered as much as possible. In this extreme case, the edge 92 ofthe part of the transverse seal that has been folded down and attachedto the second side wall 35 of the package is positioned precisely at theedge 96 of the second side wall. If the top wall were to be furtherinclined, the edge 92 of the transverse seal would project beyond theedge 96 of the second side wall which could remove some of theadvantages of the package. Of course, such a projecting seal edge couldbe folded around the side wall edge and be attached at the back wall 33of the package.

The above-described embodiment should only be seen as an example. Aperson skilled in the art realizes that the embodiments discussed can bemodified and varied in a number of ways without deviating from theinventive conception.

For instance, the forming devices described above are all constructed soas to displace the first transverse seal in relation to the longitudinalaxis of a first tube portion being arranged upstream from the firsttransverse seal. Naturally, the forming devices could be constructed inthe opposite way, i.e. so as to displace the first transverse seal inrelation to the longitudinal axis of a first tube portion being arrangeddownstream from the transverse seal.

Further, different designs of the shaping element have been combinedwith different designs of the rest of the forming device in the threeabove described exemplary embodiments. Of course, these combinations arejust examples and any other combination of shaping element and the restof the forming device is possible.

Further, in addition to the three above described different designs ofthe shaping element, it is possible to construct a shaping element whichis arranged to rotate around, and move along, an axis which is tilted soas to be parallel to the respective folding line of the tube inconnection with transverse sealing.

Also, the shaping element need not be constructed as a pivotable flapbut can have other designs. As an example, the shaping element can beconstructed as a bar transversally displaceable in a direction parallelto the transverse seals.

The volume control elements of the forming devices according to theabove described first and second embodiments are asymmetricallyjournaled with respect to the corresponding sealing elements toaccommodate a tilted tube portion. The same results could be obtained byhaving two asymmetrically designed, but symmetrically journaled, volumecontrol elements.

The above described machine comprises two forming devices moving up anddown along a respective guide to alternately transversally seal the tubeand continuously feed it downwards. However, this is just one possibledesign and the machine could be constructed in other ways. As anexample, the machine could be constructed so as comprise two endlesschain conveyors and a number of forming devices. The forming devices arehere separated so that one of the jaws is arranged along one of thechains, whereas the other jaw is correspondingly arranged at the otherchain. Further, the tube is arranged to be received in the area betweenthe chains. In this area, two correspondingly arranged jaws are arrangedto engage with each other to squeeze the tube in a flat-laid conditionand transversally seal it. One known machine of this kind is known frompatent application EP 887264. Obviously, forming devices constructed inaccordance with the present invention could be used in connection withsuch chain-based machines. In connection with both the guide design andthe chain design, solutions with symmetrical as well as asymmetricalmovement of the sealing jaws and volume control elements of each formingdevice are possible. Such asymmetrical movement could reduce stresses inthe packaging laminate.

Additionally, the inventive machine described above is arranged toproduce packages with an off-centered transverse seal and, therefore, aninclined top wall. The machine could instead be arranged to producepackages with other shapes, for example packages with both transverseseals off-centered, either in the same displacement direction or inopposite displacement directions and, therefore, inclined top and bottomwalls. Further, the packages can be formed so as to have other crosssections than rectangular in a plane parallel to the bottom wall.

Further, above the transverse sealing has been effected by means ofinduction sealing. However, any suitable technique for transversesealing could be used, such as ultrasonic sealing and hot air sealing.

As one last example, the crease pattern need not be just like the onepresented above. For example, the crease lines do not have to becontinuous or cross each other as the ones described above.

It should be pointed out that a description of details not relevant tothe invention has been omitted.

Finally, it should be pointed out that the figures are not drawnaccording to scale.

The invention claimed is:
 1. A package being made from a packaginglaminate web, said packaging laminate web comprising a crease patterncorresponding to one package and repeating itself along the web, saidpackage comprising a front wall, a back wall, first and second opposingside walls, a bottom wall and a top wall, the crease pattern comprisinga front crease line defining an extension of the front wall in alongitudinal direction of said package pointing towards the top wall andbeing parallel to the longitudinal axis of a tube formed from thepackaging laminate web, a back crease line defining an extension of theback wall in said longitudinal direction, a first side crease linedefining an extension of the first side wall in said longitudinaldirection and a second side crease line defining an extension of thesecond side wall in said longitudinal direction, wherein the first andsecond side crease lines are inclined in relation to a transversedirection of the web.
 2. A packaging laminate for forming liquid foodpackages, comprising a crease pattern corresponding to one package, saidpackage comprising a front wall, a back wall, first and second opposingside walls, a bottom wall and a top wall, the crease pattern comprisinga front crease line defining an extension of the front wall in alongitudinal direction of said final package pointing towards the topwall and being parallel to a longitudinal axis of the packaginglaminate, a back crease line defining an extension of the back wall insaid longitudinal direction, a first side crease line defining anextension of the first side wall in said longitudinal direction and asecond side crease line defining an extension of the second side wall insaid longitudinal direction, wherein the first and second side creaselines are inclined in relation to a transverse direction of thepackaging laminate.
 3. A package according to claim 1, wherein the frontand back crease lines are essentially parallel to the transversedirection of the web, the first and second side crease lines beingarranged with said predetermined angle of inclination in relation to thefront crease line.
 4. A package according to claim 1, wherein thepackaging laminate web further comprises two mutually opposinglongitudinal edge sections arranged to be joined together in anoverlapping condition for forming of a longitudinal seal and therebysaid tube, the back wall of said package comprising a part of thelongitudinal seal and said extension of the back wall being larger thansaid extension of the front wall in said longitudinal direction.
 5. Apackage according to claim 1, wherein the packaging laminate web furthercomprises first and second transverse sealing zones intended for firstand second transverse seals of the tube, respectively, the webcomprising one turn of the crease pattern between the first and secondtransverse sealing zones, a transverse web portion between the firsttransverse sealing zone and said crease lines of said one turn of thecrease pattern being arranged to form the top wall of said package aswell as first and second opposite triangular top flaps of two layerspackaging laminate, one of the layers extending from the top wall andthe other layer extending from the respective one of the first andsecond side walls, the top flaps being foldable along the respectiveside crease lines and thereafter attachable to the respective first andsecond side walls, the crease pattern further comprising a pair of topflap crease lines associated with each one of the first and second sidecrease lines, the top flap crease lines of each pair extending in saidtransverse web portion and defining two free edges of each respectivetop flap.
 6. A package according to claim 1, further comprising anopening device which dimensions are chosen so that the highest point onthe opening device lies in the same plane as the highest edge of thepackage.
 7. A package according to claim 1, wherein a transversaldistance between longitudinal crease lines, forming the longitudinaledges of the package, is equal between all crease lines.
 8. A packagebeing made from a packaging laminate as claimed in claim
 2. 9. A packageaccording to claim 8, further comprising an opening device whichdimensions are chosen so that the highest point of the opening devicelies in the same plane as the highest edge of the package.
 10. A packageaccording to claim 8, wherein transversal distances between adjacentlongitudinal crease lines, forming longitudinal edges of the package,are equal.